r.i-i LA, 



B. rnbiiiinomi ( JI.K. I -it. Hi-t.iii, p. 107. Apr., 



1849; U.S. Kxj.l. Kxprd.. p. 221, t M:il. lil. 



\\ii. p. 171.- /,V/,r ( /;//,-.,. *//W,, Ml NKI ./.. it-.-!,,-, f. M:,l ! 



I>. 188. 



I have not seen this species, which is evidently a n ar ally of A'. 

 tmyi/ilnfa, if nut identical with it. Menke thus d.-M-rili. ~ B.9U& 

 " Shell oblong-dllptioal ttinbilicated at vertex, rather solid, li-- 

 tinctly and closely, transversely striated below, longitudinally irre- 

 gularly and more or less obviously subsulcate; lip -omewhat 

 straightened in the middle; rufous ashy. Length 13, diain. 7 1 

 ////>., salt lake at S. Pedro dos Indios, ho Frio, ooai 



Brazil. The deep longitudinal furrows, always most pronounced <>n 

 the back and outer lip, distinguish this species. The- thin callus of 

 the inner lip ascends to the apical umbilicus, sometimes even in- 

 vading it." 



B. OCCIDENTALS A. Adams. PI. 38, figs. 51, 52, 53, 55, 56, 57- 



60; pi. 39, figs. 77,78. 



Shell excessively variable in size, solidity and coloring, but distin- 

 guished from B. striata by (1) the narrower umbilicus, (2) the 

 absence or obsolescence of transverse grooves near the vertex, (3) 

 the less attenuated posterior end [in all of which it is more like the 

 Algerian variety mentioned under B. striata]. It is distiiiL r u 

 from />'. 'inuft/dala by its thinner, more shining, mieroscopally spiral- 

 led shell. 



Some forms are small, very thin, fragile, subcylindrica), dei. 

 wave-striated spirally throughout, with the ba>al _i 

 differentiated (pi. 38, fig. 60, pi. :)!, f. 1*, from a Lake \V..rt! 

 Florida specimen). Some are solider, with close iebi - (pi. 



38, f. 59) as in certain Bahama shells. The prevalent form along 

 the mainland, Texas to A spin wall and Trinidad, is larger an 1 M 

 atelv solid, (1) closely mottled with reddish and whit- , 52, 



Vera Cruz) or olivaceous and whit- m.-ttled with olivace- 



ous and clouded with black and white (figs. 53, 55, 

 greso, Yucatan). In unworn examples micro-copM 1 >piral >tri.e may 

 be seen over the whole surface, and also basal spaced grooves, but 

 the latter are sometimes very weak and hardly seen on the small 

 thin forms from Florida. The coarser shells sometimes show > 



